The first thing to do is get all the batteries up to full charge. I'm not assuming they are dead, but it is a good place to start looking. Until they are at full charge (48 hours on a smart charger is a good start) there isn't much one can do.
Put a meter on the batteries and see what state they are in. If you do not have access to 120 VAC where the coach is, it will be a PITA but you may need to pull the batteries and take them to a location where a smart charger can do its' thing.
It is best if you can have the coach connected to shore power when in storage. Otherwise, does your coach have coach and chassis battery disconnect switches? If so, consider using them when the coach is in storage. In addition to the disconnect switches manually turn off the CO detector and power step switch.
2005 Newmar KSDP 3910 + GMC ENVOY XUV 37K lbs Moving Down The Road
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